Why are rivers useful for biodiversity?

Correct answer: They provide habitat to many organisms

The direct answer is A: rivers provide habitat to many organisms. Biodiversity means the variety of living organisms, including plants, fish, insects, birds, amphibians, microorganisms, and animals around a river. A river supplies water, food, breeding places, shelter, and connected habitats. Different parts—bank, shallow water, deep water, wetland, and nearby vegetation—can support different species. Therefore, a river helps many forms of life survive and interact. Option A is correct because habitat is the basic support that allows organisms to live and reproduce. Option B is wrong because rivers do not remove all organisms; although pollution may harm life, that is not the normal role of a healthy river. Option C is wrong because rivers carry sediments and water but do not produce only stones. Option D is wrong because rivers do provide water to plants along their banks and in connected ecosystems. Protecting river water and vegetation protects biodiversity. Memory cue: a healthy river is a living corridor, not just a channel of water.